This invention relates to alkyl and/or alkenyl oligoglycoside preparations with a magnesium salt concentration of less than 10 ppm which are obtained by adjusting alkyl and/or alkenyl oligoglycoside preparations to a certain pH range and then purifying them in a column charged with an ion exchange resin and to a process for the production of these preparations.
In the production of alkyl and/or alkenyl oligoglycosides by reaction of fatty alcohols with glucose, magnesium oxide is added during the synthesis. In order to ensure that alkyl and/or alkenyl oligoglycosides have high stabilities in storage without the addition of preservatives, preparations of the type in question have to be adjusted to basic pH values. At pH values above 11.3 in particular, unwanted clouding occurs or a deposit attributable to precipitation of the magnesium oxide is formed. Although treatment of the alkyl and/or alkenyl oligoglycoside preparations with complexing agents does lead to clear pastes in the interim, the magnesium salts still present in the solution may possibly be released as poorly soluble salts during subsequent processing.
Accordingly, the problem addressed by the present invention was to provide alkyl and/or alkenyl oligoglycoside preparations which would contain reduced concentrations of magnesium salts, which would also be color-stable at basic pH values and which would optionally show microbial stability and would therefore not produce any clouding over the entire pH range. In addition, the invention set out to provide a simple and inexpensive process for the production of these preparations.